server.js

require('dotenv').config()
var {
    google
} = require('googleapis');
var OAuth2 = google.auth.OAuth2;
const VIDEO_ID = process.env.VIDEO_ID

//main()

async function main() {
    try {
        const auth = authorize()
        const videoViews = await getVideoViews(auth)
        const videoTitle = await updateVideoTitle(auth, videoViews)
        console.log(videoTitle)
    } catch (e) {
        console.error(e)
    }
}

function authorize() {
    const credentials = JSON.parse(process.env.CLIENT_SECRET)
    var clientSecret = credentials.installed.client_secret;
    var clientId = credentials.installed.client_id;
    var redirectUrl = credentials.installed.redirect_uris[0];
    var oauth2Client = new OAuth2(clientId, clientSecret, redirectUrl);

    oauth2Client.credentials = JSON.parse(process.env.OAUTH_TOKEN);
    return oauth2Client
}

function getVideoViews(auth) {
    const service = google.youtube('v3')
    return new Promise((resolve, reject) => {
        service.videos.list({
            auth: auth,
            part: 'statistics',
            id: VIDEO_ID
        }, function(err, response) {
            if (err) return reject(err)
            resolve(response.data.items[0].statistics.viewCount)
        })
    })
}

function updateVideoTitle(auth, views) {
    const service = google.youtube('v3')
    return new Promise((resolve, reject) => {
        service.videos.update({
            auth: auth,
            part: 'snippet',
            resource: {
                id: VIDEO_ID,
                snippet: {
                    title: `This Video Has ${new Intl.NumberFormat('en-US').format(views)} Views`,
                    description: `Happy Coding! | ${new Intl.NumberFormat('en-US').format(views)} Views`,
                    categoryId: 27
                }
            }
        }, function(err, response) {
            if (err) return reject(err)
            resolve(response.data.snippet.title)
        })
    })
}
main();